Fossils can reveal an incredible amount of information. From what kind of organisms lived when and where to how they may have evolved over time. And now a new discovery of plant fossils with abundant fossilized charcoal reveals something new about prehistoric forest fires.

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Forest fires affect ecosystems differently and despite the fact that organisms and plant life have had to adapt to cope with these natural phenomena, new research shows that forests have been recovering from fires in the same manner as they did 66 million years ago.

According to researchers at McGill University and the Royal Saskatchewan Museum, an expedition in southern Saskatchewan, Canada revealed a snapshot of the ecology on earth just before the mass extinction of the dinosaurs. The researchers also found evidence that the region's climate was much warmer and wetter than it is today.

"We were able to reconstruct what the Cretaceous forests looked like with and without fire disturbance", says Hans Larsson, Canada Research Chair in Macroevolution at McGill University.

The researchers' discovery revealed that at the forest fire site, the plants are dominated by flora quite similar to the kind that begin forest recovery after a fire today. Ancient forests recovered much like current ones, with plants like alder, birch, and sassafras present in early stages, and sequoia and ginkgo present in mature forests.

"We were looking at the direct result of a 66-million-year old forest fire, preserved in stone," says Emily Bamforth, of the Royal Saskatchewan Museum and the study's first author. "Moreover, we now have evidence that the mean annual temperature in southern Saskatchewan was 10-12 degrees Celsius warmer than today, with almost six times as much precipitation".

"The abundant plant fossils also allowed us for the first time to estimate climate conditions for the closing period of the dinosaurs in southwestern Canada, and provides one more clue to reveal what the ecology was like just before they went extinct", says Larsson, who is also an Associate Professor at the Redpath Museum.

The team's finding of ancient ecological recovery from a forest fire will help broaden scientists' understanding of biodiversity immediately before the mass extinction of dinosaurs. "We won't be able to fully understand the extinction dynamics until we understand what normal ecological processes were going on in the background," says Larsson.